xref: /freebsd/sys/dev/gem/if_gem.c (revision 54ebdd631db8c0bba2baab0155f603a8b5cf014a)
1 /*-
2  * Copyright (C) 2001 Eduardo Horvath.
3  * Copyright (c) 2001-2003 Thomas Moestl
4  * Copyright (c) 2007 Marius Strobl <marius@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR  ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR  BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  *	from: NetBSD: gem.c,v 1.21 2002/06/01 23:50:58 lukem Exp
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 /*
35  * Driver for Apple GMAC, Sun ERI and Sun GEM Ethernet controllers
36  */
37 
38 #if 0
39 #define	GEM_DEBUG
40 #endif
41 
42 #if 0	/* XXX: In case of emergency, re-enable this. */
43 #define	GEM_RINT_TIMEOUT
44 #endif
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/bus.h>
49 #include <sys/callout.h>
50 #include <sys/endian.h>
51 #include <sys/mbuf.h>
52 #include <sys/malloc.h>
53 #include <sys/kernel.h>
54 #include <sys/lock.h>
55 #include <sys/module.h>
56 #include <sys/mutex.h>
57 #include <sys/socket.h>
58 #include <sys/sockio.h>
59 #include <sys/rman.h>
60 
61 #include <net/bpf.h>
62 #include <net/ethernet.h>
63 #include <net/if.h>
64 #include <net/if_arp.h>
65 #include <net/if_dl.h>
66 #include <net/if_media.h>
67 #include <net/if_types.h>
68 #include <net/if_vlan_var.h>
69 
70 #include <netinet/in.h>
71 #include <netinet/in_systm.h>
72 #include <netinet/ip.h>
73 #include <netinet/tcp.h>
74 #include <netinet/udp.h>
75 
76 #include <machine/bus.h>
77 
78 #include <dev/mii/mii.h>
79 #include <dev/mii/miivar.h>
80 
81 #include <dev/gem/if_gemreg.h>
82 #include <dev/gem/if_gemvar.h>
83 
84 CTASSERT(powerof2(GEM_NRXDESC) && GEM_NRXDESC >= 32 && GEM_NRXDESC <= 8192);
85 CTASSERT(powerof2(GEM_NTXDESC) && GEM_NTXDESC >= 32 && GEM_NTXDESC <= 8192);
86 
87 #define	TRIES	10000
88 
89 /*
90  * The hardware supports basic TCP/UDP checksum offloading.  However,
91  * the hardware doesn't compensate the checksum for UDP datagram which
92  * can yield to 0x0.  As a safe guard, UDP checksum offload is disabled
93  * by default.  It can be reactivated by setting special link option
94  * link0 with ifconfig(8).
95  */
96 #define	GEM_CSUM_FEATURES	(CSUM_TCP)
97 
98 static int	gem_add_rxbuf(struct gem_softc *sc, int idx);
99 static int	gem_bitwait(struct gem_softc *sc, u_int bank, bus_addr_t r,
100 		    uint32_t clr, uint32_t set);
101 static void	gem_cddma_callback(void *xsc, bus_dma_segment_t *segs,
102 		    int nsegs, int error);
103 static int	gem_disable_rx(struct gem_softc *sc);
104 static int	gem_disable_tx(struct gem_softc *sc);
105 static void	gem_eint(struct gem_softc *sc, u_int status);
106 static void	gem_init(void *xsc);
107 static void	gem_init_locked(struct gem_softc *sc);
108 static void	gem_init_regs(struct gem_softc *sc);
109 static int	gem_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data);
110 static int	gem_load_txmbuf(struct gem_softc *sc, struct mbuf **m_head);
111 static int	gem_meminit(struct gem_softc *sc);
112 static void	gem_mifinit(struct gem_softc *sc);
113 static void	gem_reset(struct gem_softc *sc);
114 static int	gem_reset_rx(struct gem_softc *sc);
115 static void	gem_reset_rxdma(struct gem_softc *sc);
116 static int	gem_reset_tx(struct gem_softc *sc);
117 static u_int	gem_ringsize(u_int sz);
118 static void	gem_rint(struct gem_softc *sc);
119 #ifdef GEM_RINT_TIMEOUT
120 static void	gem_rint_timeout(void *arg);
121 #endif
122 static __inline void gem_rxcksum(struct mbuf *m, uint64_t flags);
123 static void	gem_rxdrain(struct gem_softc *sc);
124 static void	gem_setladrf(struct gem_softc *sc);
125 static void	gem_start(struct ifnet *ifp);
126 static void	gem_start_locked(struct ifnet *ifp);
127 static void	gem_stop(struct ifnet *ifp, int disable);
128 static void	gem_tick(void *arg);
129 static void	gem_tint(struct gem_softc *sc);
130 static int	gem_watchdog(struct gem_softc *sc);
131 
132 devclass_t gem_devclass;
133 DRIVER_MODULE(miibus, gem, miibus_driver, miibus_devclass, 0, 0);
134 MODULE_DEPEND(gem, miibus, 1, 1, 1);
135 
136 #ifdef GEM_DEBUG
137 #include <sys/ktr.h>
138 #define	KTR_GEM		KTR_CT2
139 #endif
140 
141 #define	GEM_BANK1_BITWAIT(sc, r, clr, set)				\
142 	gem_bitwait((sc), GEM_RES_BANK1, (r), (clr), (set))
143 #define	GEM_BANK2_BITWAIT(sc, r, clr, set)				\
144 	gem_bitwait((sc), GEM_RES_BANK2, (r), (clr), (set))
145 
146 int
147 gem_attach(struct gem_softc *sc)
148 {
149 	struct gem_txsoft *txs;
150 	struct ifnet *ifp;
151 	int error, i;
152 	uint32_t v;
153 
154 	ifp = sc->sc_ifp = if_alloc(IFT_ETHER);
155 	if (ifp == NULL)
156 		return (ENOSPC);
157 
158 	callout_init_mtx(&sc->sc_tick_ch, &sc->sc_mtx, 0);
159 #ifdef GEM_RINT_TIMEOUT
160 	callout_init_mtx(&sc->sc_rx_ch, &sc->sc_mtx, 0);
161 #endif
162 
163 	/* Make sure the chip is stopped. */
164 	ifp->if_softc = sc;
165 	gem_reset(sc);
166 
167 	error = bus_dma_tag_create(bus_get_dma_tag(sc->sc_dev), 1, 0,
168 	    BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL,
169 	    BUS_SPACE_MAXSIZE_32BIT, 0, BUS_SPACE_MAXSIZE_32BIT, 0, NULL,
170 	    NULL, &sc->sc_pdmatag);
171 	if (error)
172 		goto fail_ifnet;
173 
174 	error = bus_dma_tag_create(sc->sc_pdmatag, 1, 0,
175 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL, MCLBYTES,
176 	    1, MCLBYTES, BUS_DMA_ALLOCNOW, NULL, NULL, &sc->sc_rdmatag);
177 	if (error)
178 		goto fail_ptag;
179 
180 	error = bus_dma_tag_create(sc->sc_pdmatag, 1, 0,
181 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
182 	    MCLBYTES * GEM_NTXSEGS, GEM_NTXSEGS, MCLBYTES,
183 	    BUS_DMA_ALLOCNOW, NULL, NULL, &sc->sc_tdmatag);
184 	if (error)
185 		goto fail_rtag;
186 
187 	error = bus_dma_tag_create(sc->sc_pdmatag, PAGE_SIZE, 0,
188 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
189 	    sizeof(struct gem_control_data), 1,
190 	    sizeof(struct gem_control_data), 0,
191 	    NULL, NULL, &sc->sc_cdmatag);
192 	if (error)
193 		goto fail_ttag;
194 
195 	/*
196 	 * Allocate the control data structures, create and load the
197 	 * DMA map for it.
198 	 */
199 	if ((error = bus_dmamem_alloc(sc->sc_cdmatag,
200 	    (void **)&sc->sc_control_data,
201 	    BUS_DMA_WAITOK | BUS_DMA_COHERENT | BUS_DMA_ZERO,
202 	    &sc->sc_cddmamap))) {
203 		device_printf(sc->sc_dev,
204 		    "unable to allocate control data, error = %d\n", error);
205 		goto fail_ctag;
206 	}
207 
208 	sc->sc_cddma = 0;
209 	if ((error = bus_dmamap_load(sc->sc_cdmatag, sc->sc_cddmamap,
210 	    sc->sc_control_data, sizeof(struct gem_control_data),
211 	    gem_cddma_callback, sc, 0)) != 0 || sc->sc_cddma == 0) {
212 		device_printf(sc->sc_dev,
213 		    "unable to load control data DMA map, error = %d\n",
214 		    error);
215 		goto fail_cmem;
216 	}
217 
218 	/*
219 	 * Initialize the transmit job descriptors.
220 	 */
221 	STAILQ_INIT(&sc->sc_txfreeq);
222 	STAILQ_INIT(&sc->sc_txdirtyq);
223 
224 	/*
225 	 * Create the transmit buffer DMA maps.
226 	 */
227 	error = ENOMEM;
228 	for (i = 0; i < GEM_TXQUEUELEN; i++) {
229 		txs = &sc->sc_txsoft[i];
230 		txs->txs_mbuf = NULL;
231 		txs->txs_ndescs = 0;
232 		if ((error = bus_dmamap_create(sc->sc_tdmatag, 0,
233 		    &txs->txs_dmamap)) != 0) {
234 			device_printf(sc->sc_dev,
235 			    "unable to create TX DMA map %d, error = %d\n",
236 			    i, error);
237 			goto fail_txd;
238 		}
239 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
240 	}
241 
242 	/*
243 	 * Create the receive buffer DMA maps.
244 	 */
245 	for (i = 0; i < GEM_NRXDESC; i++) {
246 		if ((error = bus_dmamap_create(sc->sc_rdmatag, 0,
247 		    &sc->sc_rxsoft[i].rxs_dmamap)) != 0) {
248 			device_printf(sc->sc_dev,
249 			    "unable to create RX DMA map %d, error = %d\n",
250 			    i, error);
251 			goto fail_rxd;
252 		}
253 		sc->sc_rxsoft[i].rxs_mbuf = NULL;
254 	}
255 
256 	/* Bad things will happen when touching this register on ERI. */
257 	if (sc->sc_variant != GEM_SUN_ERI)
258 		GEM_BANK1_WRITE_4(sc, GEM_MII_DATAPATH_MODE,
259 		    GEM_MII_DATAPATH_MII);
260 
261 	gem_mifinit(sc);
262 
263 	/*
264 	 * Look for an external PHY.
265 	 */
266 	error = ENXIO;
267 	v = GEM_BANK1_READ_4(sc, GEM_MIF_CONFIG);
268 	if ((v & GEM_MIF_CONFIG_MDI1) != 0) {
269 		v |= GEM_MIF_CONFIG_PHY_SEL;
270 		GEM_BANK1_WRITE_4(sc, GEM_MIF_CONFIG, v);
271 		switch (sc->sc_variant) {
272 		case GEM_SUN_ERI:
273 			sc->sc_phyad = GEM_PHYAD_EXTERNAL;
274 			break;
275 		default:
276 			sc->sc_phyad = -1;
277 			break;
278 		}
279 		error = mii_phy_probe(sc->sc_dev, &sc->sc_miibus,
280 		    gem_mediachange, gem_mediastatus);
281 	}
282 
283 	/*
284 	 * Fall back on an internal PHY if no external PHY was found.
285 	 */
286 	if (error != 0 && (v & GEM_MIF_CONFIG_MDI0) != 0) {
287 		v &= ~GEM_MIF_CONFIG_PHY_SEL;
288 		GEM_BANK1_WRITE_4(sc, GEM_MIF_CONFIG, v);
289 		switch (sc->sc_variant) {
290 		case GEM_SUN_ERI:
291 		case GEM_APPLE_K2_GMAC:
292 			sc->sc_phyad = GEM_PHYAD_INTERNAL;
293 			break;
294 		case GEM_APPLE_GMAC:
295 			sc->sc_phyad = GEM_PHYAD_EXTERNAL;
296 			break;
297 		default:
298 			sc->sc_phyad = -1;
299 			break;
300 		}
301 		error = mii_phy_probe(sc->sc_dev, &sc->sc_miibus,
302 		    gem_mediachange, gem_mediastatus);
303 	}
304 
305 	/*
306 	 * Try the external PCS SERDES if we didn't find any PHYs.
307 	 */
308 	if (error != 0 && sc->sc_variant == GEM_SUN_GEM) {
309 		GEM_BANK1_WRITE_4(sc, GEM_MII_DATAPATH_MODE,
310 		    GEM_MII_DATAPATH_SERDES);
311 		GEM_BANK1_WRITE_4(sc, GEM_MII_SLINK_CONTROL,
312 		    GEM_MII_SLINK_LOOPBACK | GEM_MII_SLINK_EN_SYNC_D);
313 		GEM_BANK1_WRITE_4(sc, GEM_MII_CONFIG, GEM_MII_CONFIG_ENABLE);
314 		sc->sc_flags |= GEM_SERDES;
315 		sc->sc_phyad = GEM_PHYAD_EXTERNAL;
316 		error = mii_phy_probe(sc->sc_dev, &sc->sc_miibus,
317 		    gem_mediachange, gem_mediastatus);
318 	}
319 
320 	if (error != 0) {
321 		device_printf(sc->sc_dev, "PHY probe failed: %d\n", error);
322 		goto fail_rxd;
323 	}
324 	sc->sc_mii = device_get_softc(sc->sc_miibus);
325 
326 	/*
327 	 * From this point forward, the attachment cannot fail.  A failure
328 	 * before this point releases all resources that may have been
329 	 * allocated.
330 	 */
331 
332 	/* Get RX FIFO size. */
333 	sc->sc_rxfifosize = 64 *
334 	    GEM_BANK1_READ_4(sc, GEM_RX_FIFO_SIZE);
335 
336 	/* Get TX FIFO size. */
337 	v = GEM_BANK1_READ_4(sc, GEM_TX_FIFO_SIZE);
338 	device_printf(sc->sc_dev, "%ukB RX FIFO, %ukB TX FIFO\n",
339 	    sc->sc_rxfifosize / 1024, v / 16);
340 
341 	sc->sc_csum_features = GEM_CSUM_FEATURES;
342 	/* Initialize ifnet structure. */
343 	ifp->if_softc = sc;
344 	if_initname(ifp, device_get_name(sc->sc_dev),
345 	    device_get_unit(sc->sc_dev));
346 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
347 	ifp->if_start = gem_start;
348 	ifp->if_ioctl = gem_ioctl;
349 	ifp->if_init = gem_init;
350 	IFQ_SET_MAXLEN(&ifp->if_snd, GEM_TXQUEUELEN);
351 	ifp->if_snd.ifq_drv_maxlen = GEM_TXQUEUELEN;
352 	IFQ_SET_READY(&ifp->if_snd);
353 
354 	/* Attach the interface. */
355 	ether_ifattach(ifp, sc->sc_enaddr);
356 
357 	/*
358 	 * Tell the upper layer(s) we support long frames/checksum offloads.
359 	 */
360 	ifp->if_data.ifi_hdrlen = sizeof(struct ether_vlan_header);
361 	ifp->if_capabilities |= IFCAP_VLAN_MTU | IFCAP_HWCSUM;
362 	ifp->if_hwassist |= sc->sc_csum_features;
363 	ifp->if_capenable |= IFCAP_VLAN_MTU | IFCAP_HWCSUM;
364 
365 	return (0);
366 
367 	/*
368 	 * Free any resources we've allocated during the failed attach
369 	 * attempt.  Do this in reverse order and fall through.
370 	 */
371  fail_rxd:
372 	for (i = 0; i < GEM_NRXDESC; i++)
373 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
374 			bus_dmamap_destroy(sc->sc_rdmatag,
375 			    sc->sc_rxsoft[i].rxs_dmamap);
376  fail_txd:
377 	for (i = 0; i < GEM_TXQUEUELEN; i++)
378 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
379 			bus_dmamap_destroy(sc->sc_tdmatag,
380 			    sc->sc_txsoft[i].txs_dmamap);
381 	bus_dmamap_unload(sc->sc_cdmatag, sc->sc_cddmamap);
382  fail_cmem:
383 	bus_dmamem_free(sc->sc_cdmatag, sc->sc_control_data,
384 	    sc->sc_cddmamap);
385  fail_ctag:
386 	bus_dma_tag_destroy(sc->sc_cdmatag);
387  fail_ttag:
388 	bus_dma_tag_destroy(sc->sc_tdmatag);
389  fail_rtag:
390 	bus_dma_tag_destroy(sc->sc_rdmatag);
391  fail_ptag:
392 	bus_dma_tag_destroy(sc->sc_pdmatag);
393  fail_ifnet:
394 	if_free(ifp);
395 	return (error);
396 }
397 
398 void
399 gem_detach(struct gem_softc *sc)
400 {
401 	struct ifnet *ifp = sc->sc_ifp;
402 	int i;
403 
404 	GEM_LOCK(sc);
405 	gem_stop(ifp, 1);
406 	GEM_UNLOCK(sc);
407 	callout_drain(&sc->sc_tick_ch);
408 #ifdef GEM_RINT_TIMEOUT
409 	callout_drain(&sc->sc_rx_ch);
410 #endif
411 	ether_ifdetach(ifp);
412 	if_free(ifp);
413 	device_delete_child(sc->sc_dev, sc->sc_miibus);
414 
415 	for (i = 0; i < GEM_NRXDESC; i++)
416 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
417 			bus_dmamap_destroy(sc->sc_rdmatag,
418 			    sc->sc_rxsoft[i].rxs_dmamap);
419 	for (i = 0; i < GEM_TXQUEUELEN; i++)
420 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
421 			bus_dmamap_destroy(sc->sc_tdmatag,
422 			    sc->sc_txsoft[i].txs_dmamap);
423 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
424 	bus_dmamap_unload(sc->sc_cdmatag, sc->sc_cddmamap);
425 	bus_dmamem_free(sc->sc_cdmatag, sc->sc_control_data,
426 	    sc->sc_cddmamap);
427 	bus_dma_tag_destroy(sc->sc_cdmatag);
428 	bus_dma_tag_destroy(sc->sc_tdmatag);
429 	bus_dma_tag_destroy(sc->sc_rdmatag);
430 	bus_dma_tag_destroy(sc->sc_pdmatag);
431 }
432 
433 void
434 gem_suspend(struct gem_softc *sc)
435 {
436 	struct ifnet *ifp = sc->sc_ifp;
437 
438 	GEM_LOCK(sc);
439 	gem_stop(ifp, 0);
440 	GEM_UNLOCK(sc);
441 }
442 
443 void
444 gem_resume(struct gem_softc *sc)
445 {
446 	struct ifnet *ifp = sc->sc_ifp;
447 
448 	GEM_LOCK(sc);
449 	/*
450 	 * On resume all registers have to be initialized again like
451 	 * after power-on.
452 	 */
453 	sc->sc_flags &= ~GEM_INITED;
454 	if (ifp->if_flags & IFF_UP)
455 		gem_init_locked(sc);
456 	GEM_UNLOCK(sc);
457 }
458 
459 static __inline void
460 gem_rxcksum(struct mbuf *m, uint64_t flags)
461 {
462 	struct ether_header *eh;
463 	struct ip *ip;
464 	struct udphdr *uh;
465 	uint16_t *opts;
466 	int32_t hlen, len, pktlen;
467 	uint32_t temp32;
468 	uint16_t cksum;
469 
470 	pktlen = m->m_pkthdr.len;
471 	if (pktlen < sizeof(struct ether_header) + sizeof(struct ip))
472 		return;
473 	eh = mtod(m, struct ether_header *);
474 	if (eh->ether_type != htons(ETHERTYPE_IP))
475 		return;
476 	ip = (struct ip *)(eh + 1);
477 	if (ip->ip_v != IPVERSION)
478 		return;
479 
480 	hlen = ip->ip_hl << 2;
481 	pktlen -= sizeof(struct ether_header);
482 	if (hlen < sizeof(struct ip))
483 		return;
484 	if (ntohs(ip->ip_len) < hlen)
485 		return;
486 	if (ntohs(ip->ip_len) != pktlen)
487 		return;
488 	if (ip->ip_off & htons(IP_MF | IP_OFFMASK))
489 		return;	/* Cannot handle fragmented packet. */
490 
491 	switch (ip->ip_p) {
492 	case IPPROTO_TCP:
493 		if (pktlen < (hlen + sizeof(struct tcphdr)))
494 			return;
495 		break;
496 	case IPPROTO_UDP:
497 		if (pktlen < (hlen + sizeof(struct udphdr)))
498 			return;
499 		uh = (struct udphdr *)((uint8_t *)ip + hlen);
500 		if (uh->uh_sum == 0)
501 			return; /* no checksum */
502 		break;
503 	default:
504 		return;
505 	}
506 
507 	cksum = ~(flags & GEM_RD_CHECKSUM);
508 	/* checksum fixup for IP options */
509 	len = hlen - sizeof(struct ip);
510 	if (len > 0) {
511 		opts = (uint16_t *)(ip + 1);
512 		for (; len > 0; len -= sizeof(uint16_t), opts++) {
513 			temp32 = cksum - *opts;
514 			temp32 = (temp32 >> 16) + (temp32 & 65535);
515 			cksum = temp32 & 65535;
516 		}
517 	}
518 	m->m_pkthdr.csum_flags |= CSUM_DATA_VALID;
519 	m->m_pkthdr.csum_data = cksum;
520 }
521 
522 static void
523 gem_cddma_callback(void *xsc, bus_dma_segment_t *segs, int nsegs, int error)
524 {
525 	struct gem_softc *sc = xsc;
526 
527 	if (error != 0)
528 		return;
529 	if (nsegs != 1)
530 		panic("%s: bad control buffer segment count", __func__);
531 	sc->sc_cddma = segs[0].ds_addr;
532 }
533 
534 static void
535 gem_tick(void *arg)
536 {
537 	struct gem_softc *sc = arg;
538 	struct ifnet *ifp;
539 	uint32_t v;
540 
541 	GEM_LOCK_ASSERT(sc, MA_OWNED);
542 
543 	ifp = sc->sc_ifp;
544 	/*
545 	 * Unload collision and error counters.
546 	 */
547 	ifp->if_collisions +=
548 	    GEM_BANK1_READ_4(sc, GEM_MAC_NORM_COLL_CNT) +
549 	    GEM_BANK1_READ_4(sc, GEM_MAC_FIRST_COLL_CNT);
550 	v = GEM_BANK1_READ_4(sc, GEM_MAC_EXCESS_COLL_CNT) +
551 	    GEM_BANK1_READ_4(sc, GEM_MAC_LATE_COLL_CNT);
552 	ifp->if_collisions += v;
553 	ifp->if_oerrors += v;
554 	ifp->if_ierrors +=
555 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_LEN_ERR_CNT) +
556 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_ALIGN_ERR) +
557 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CRC_ERR_CNT) +
558 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CODE_VIOL);
559 
560 	/*
561 	 * Then clear the hardware counters.
562 	 */
563 	GEM_BANK1_WRITE_4(sc, GEM_MAC_NORM_COLL_CNT, 0);
564 	GEM_BANK1_WRITE_4(sc, GEM_MAC_FIRST_COLL_CNT, 0);
565 	GEM_BANK1_WRITE_4(sc, GEM_MAC_EXCESS_COLL_CNT, 0);
566 	GEM_BANK1_WRITE_4(sc, GEM_MAC_LATE_COLL_CNT, 0);
567 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_LEN_ERR_CNT, 0);
568 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_ALIGN_ERR, 0);
569 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CRC_ERR_CNT, 0);
570 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CODE_VIOL, 0);
571 
572 	mii_tick(sc->sc_mii);
573 
574 	if (gem_watchdog(sc) == EJUSTRETURN)
575 		return;
576 
577 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
578 }
579 
580 static int
581 gem_bitwait(struct gem_softc *sc, u_int bank, bus_addr_t r, uint32_t clr,
582     uint32_t set)
583 {
584 	int i;
585 	uint32_t reg;
586 
587 	for (i = TRIES; i--; DELAY(100)) {
588 		reg = GEM_BANKN_READ_M(bank, 4, sc, r);
589 		if ((reg & clr) == 0 && (reg & set) == set)
590 			return (1);
591 	}
592 	return (0);
593 }
594 
595 static void
596 gem_reset(sc)
597 	struct gem_softc *sc;
598 {
599 
600 #ifdef GEM_DEBUG
601 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
602 #endif
603 	gem_reset_rx(sc);
604 	gem_reset_tx(sc);
605 
606 	/* Do a full reset. */
607 	GEM_BANK2_WRITE_4(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX);
608 	GEM_BANK2_BARRIER(sc, GEM_RESET, 4,
609 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
610 	if (!GEM_BANK2_BITWAIT(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX, 0))
611 		device_printf(sc->sc_dev, "cannot reset device\n");
612 }
613 
614 static void
615 gem_rxdrain(struct gem_softc *sc)
616 {
617 	struct gem_rxsoft *rxs;
618 	int i;
619 
620 	for (i = 0; i < GEM_NRXDESC; i++) {
621 		rxs = &sc->sc_rxsoft[i];
622 		if (rxs->rxs_mbuf != NULL) {
623 			bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
624 			    BUS_DMASYNC_POSTREAD);
625 			bus_dmamap_unload(sc->sc_rdmatag, rxs->rxs_dmamap);
626 			m_freem(rxs->rxs_mbuf);
627 			rxs->rxs_mbuf = NULL;
628 		}
629 	}
630 }
631 
632 static void
633 gem_stop(struct ifnet *ifp, int disable)
634 {
635 	struct gem_softc *sc = ifp->if_softc;
636 	struct gem_txsoft *txs;
637 
638 #ifdef GEM_DEBUG
639 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
640 #endif
641 
642 	callout_stop(&sc->sc_tick_ch);
643 #ifdef GEM_RINT_TIMEOUT
644 	callout_stop(&sc->sc_rx_ch);
645 #endif
646 
647 	/* XXX should we reset these instead? */
648 	gem_disable_tx(sc);
649 	gem_disable_rx(sc);
650 
651 	/*
652 	 * Release any queued transmit buffers.
653 	 */
654 	while ((txs = STAILQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
655 		STAILQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
656 		if (txs->txs_ndescs != 0) {
657 			bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
658 			    BUS_DMASYNC_POSTWRITE);
659 			bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
660 			if (txs->txs_mbuf != NULL) {
661 				m_freem(txs->txs_mbuf);
662 				txs->txs_mbuf = NULL;
663 			}
664 		}
665 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
666 	}
667 
668 	if (disable)
669 		gem_rxdrain(sc);
670 
671 	/*
672 	 * Mark the interface down and cancel the watchdog timer.
673 	 */
674 	ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
675 	sc->sc_flags &= ~GEM_LINK;
676 	sc->sc_wdog_timer = 0;
677 }
678 
679 static int
680 gem_reset_rx(struct gem_softc *sc)
681 {
682 
683 	/*
684 	 * Resetting while DMA is in progress can cause a bus hang, so we
685 	 * disable DMA first.
686 	 */
687 	gem_disable_rx(sc);
688 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG, 0);
689 	GEM_BANK1_BARRIER(sc, GEM_RX_CONFIG, 4,
690 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
691 	if (!GEM_BANK1_BITWAIT(sc, GEM_RX_CONFIG, GEM_RX_CONFIG_RXDMA_EN, 0))
692 		device_printf(sc->sc_dev, "cannot disable RX DMA\n");
693 
694 	/* Finally, reset the ERX. */
695 	GEM_BANK2_WRITE_4(sc, GEM_RESET, GEM_RESET_RX);
696 	GEM_BANK2_BARRIER(sc, GEM_RESET, 4,
697 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
698 	if (!GEM_BANK2_BITWAIT(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX,
699 	    0)) {
700 		device_printf(sc->sc_dev, "cannot reset receiver\n");
701 		return (1);
702 	}
703 	return (0);
704 }
705 
706 /*
707  * Reset the receiver DMA engine.
708  *
709  * Intended to be used in case of GEM_INTR_RX_TAG_ERR, GEM_MAC_RX_OVERFLOW
710  * etc in order to reset the receiver DMA engine only and not do a full
711  * reset which amongst others also downs the link and clears the FIFOs.
712  */
713 static void
714 gem_reset_rxdma(struct gem_softc *sc)
715 {
716 	int i;
717 
718 	if (gem_reset_rx(sc) != 0)
719 		return (gem_init_locked(sc));
720 	for (i = 0; i < GEM_NRXDESC; i++)
721 		if (sc->sc_rxsoft[i].rxs_mbuf != NULL)
722 			GEM_UPDATE_RXDESC(sc, i);
723 	sc->sc_rxptr = 0;
724 	GEM_CDSYNC(sc, BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
725 
726 	/* NOTE: we use only 32-bit DMA addresses here. */
727 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_HI, 0);
728 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_LO, GEM_CDRXADDR(sc, 0));
729 	GEM_BANK1_WRITE_4(sc, GEM_RX_KICK, GEM_NRXDESC - 4);
730 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG,
731 	    gem_ringsize(GEM_NRXDESC /* XXX */) |
732 	    ((ETHER_HDR_LEN + sizeof(struct ip)) <<
733 	    GEM_RX_CONFIG_CXM_START_SHFT) |
734 	    (GEM_THRSH_1024 << GEM_RX_CONFIG_FIFO_THRS_SHIFT) |
735 	    (2 << GEM_RX_CONFIG_FBOFF_SHFT));
736 	GEM_BANK1_WRITE_4(sc, GEM_RX_BLANKING,
737 	    (6 << GEM_RX_BLANKING_TIME_SHIFT) | 6);
738 	GEM_BANK1_WRITE_4(sc, GEM_RX_PAUSE_THRESH,
739 	    (3 * sc->sc_rxfifosize / 256) |
740 	    ((sc->sc_rxfifosize / 256) << 12));
741 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG,
742 	    GEM_BANK1_READ_4(sc, GEM_RX_CONFIG) | GEM_RX_CONFIG_RXDMA_EN);
743 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_MASK,
744 	    GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT);
745 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG,
746 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG) | GEM_MAC_RX_ENABLE);
747 }
748 
749 static int
750 gem_reset_tx(struct gem_softc *sc)
751 {
752 
753 	/*
754 	 * Resetting while DMA is in progress can cause a bus hang, so we
755 	 * disable DMA first.
756 	 */
757 	gem_disable_tx(sc);
758 	GEM_BANK1_WRITE_4(sc, GEM_TX_CONFIG, 0);
759 	GEM_BANK1_BARRIER(sc, GEM_TX_CONFIG, 4,
760 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
761 	if (!GEM_BANK1_BITWAIT(sc, GEM_TX_CONFIG, GEM_TX_CONFIG_TXDMA_EN, 0))
762 		device_printf(sc->sc_dev, "cannot disable TX DMA\n");
763 
764 	/* Finally, reset the ETX. */
765 	GEM_BANK2_WRITE_4(sc, GEM_RESET, GEM_RESET_TX);
766 	GEM_BANK2_BARRIER(sc, GEM_RESET, 4,
767 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
768 	if (!GEM_BANK2_BITWAIT(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX,
769 	    0)) {
770 		device_printf(sc->sc_dev, "cannot reset transmitter\n");
771 		return (1);
772 	}
773 	return (0);
774 }
775 
776 static int
777 gem_disable_rx(struct gem_softc *sc)
778 {
779 
780 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG,
781 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG) & ~GEM_MAC_RX_ENABLE);
782 	GEM_BANK1_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
783 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
784 	return (GEM_BANK1_BITWAIT(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_ENABLE,
785 	    0));
786 }
787 
788 static int
789 gem_disable_tx(struct gem_softc *sc)
790 {
791 
792 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG,
793 	    GEM_BANK1_READ_4(sc, GEM_MAC_TX_CONFIG) & ~GEM_MAC_TX_ENABLE);
794 	GEM_BANK1_BARRIER(sc, GEM_MAC_TX_CONFIG, 4,
795 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
796 	return (GEM_BANK1_BITWAIT(sc, GEM_MAC_TX_CONFIG, GEM_MAC_TX_ENABLE,
797 	    0));
798 }
799 
800 static int
801 gem_meminit(sc)
802 	struct gem_softc *sc;
803 {
804 	struct gem_rxsoft *rxs;
805 	int error, i;
806 
807 	/*
808 	 * Initialize the transmit descriptor ring.
809 	 */
810 	for (i = 0; i < GEM_NTXDESC; i++) {
811 		sc->sc_txdescs[i].gd_flags = 0;
812 		sc->sc_txdescs[i].gd_addr = 0;
813 	}
814 	sc->sc_txfree = GEM_MAXTXFREE;
815 	sc->sc_txnext = 0;
816 	sc->sc_txwin = 0;
817 
818 	/*
819 	 * Initialize the receive descriptor and receive job
820 	 * descriptor rings.
821 	 */
822 	for (i = 0; i < GEM_NRXDESC; i++) {
823 		rxs = &sc->sc_rxsoft[i];
824 		if (rxs->rxs_mbuf == NULL) {
825 			if ((error = gem_add_rxbuf(sc, i)) != 0) {
826 				device_printf(sc->sc_dev,
827 				    "unable to allocate or map RX buffer %d, "
828 				    "error = %d\n", i, error);
829 				/*
830 				 * XXX we should attempt to run with fewer
831 				 * receive buffers instead of just failing.
832 				 */
833 				gem_rxdrain(sc);
834 				return (1);
835 			}
836 		} else
837 			GEM_INIT_RXDESC(sc, i);
838 	}
839 	sc->sc_rxptr = 0;
840 	GEM_CDSYNC(sc, BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
841 
842 	return (0);
843 }
844 
845 static u_int
846 gem_ringsize(u_int sz)
847 {
848 
849 	switch (sz) {
850 	case 32:
851 		return (GEM_RING_SZ_32);
852 	case 64:
853 		return (GEM_RING_SZ_64);
854 	case 128:
855 		return (GEM_RING_SZ_128);
856 	case 256:
857 		return (GEM_RING_SZ_256);
858 	case 512:
859 		return (GEM_RING_SZ_512);
860 	case 1024:
861 		return (GEM_RING_SZ_1024);
862 	case 2048:
863 		return (GEM_RING_SZ_2048);
864 	case 4096:
865 		return (GEM_RING_SZ_4096);
866 	case 8192:
867 		return (GEM_RING_SZ_8192);
868 	default:
869 		printf("%s: invalid ring size %d\n", __func__, sz);
870 		return (GEM_RING_SZ_32);
871 	}
872 }
873 
874 static void
875 gem_init(void *xsc)
876 {
877 	struct gem_softc *sc = xsc;
878 
879 	GEM_LOCK(sc);
880 	gem_init_locked(sc);
881 	GEM_UNLOCK(sc);
882 }
883 
884 /*
885  * Initialization of interface; set up initialization block
886  * and transmit/receive descriptor rings.
887  */
888 static void
889 gem_init_locked(struct gem_softc *sc)
890 {
891 	struct ifnet *ifp = sc->sc_ifp;
892 	uint32_t v;
893 
894 	GEM_LOCK_ASSERT(sc, MA_OWNED);
895 
896 #ifdef GEM_DEBUG
897 	CTR2(KTR_GEM, "%s: %s: calling stop", device_get_name(sc->sc_dev),
898 	    __func__);
899 #endif
900 	/*
901 	 * Initialization sequence.  The numbered steps below correspond
902 	 * to the sequence outlined in section 6.3.5.1 in the Ethernet
903 	 * Channel Engine manual (part of the PCIO manual).
904 	 * See also the STP2002-STQ document from Sun Microsystems.
905 	 */
906 
907 	/* step 1 & 2.  Reset the Ethernet Channel. */
908 	gem_stop(ifp, 0);
909 	gem_reset(sc);
910 #ifdef GEM_DEBUG
911 	CTR2(KTR_GEM, "%s: %s: restarting", device_get_name(sc->sc_dev),
912 	    __func__);
913 #endif
914 
915 	/* Re-initialize the MIF. */
916 	gem_mifinit(sc);
917 
918 	/* step 3.  Setup data structures in host memory. */
919 	if (gem_meminit(sc) != 0)
920 		return;
921 
922 	/* step 4.  TX MAC registers & counters */
923 	gem_init_regs(sc);
924 
925 	/* step 5.  RX MAC registers & counters */
926 	gem_setladrf(sc);
927 
928 	/* step 6 & 7.  Program Descriptor Ring Base Addresses. */
929 	/* NOTE: we use only 32-bit DMA addresses here. */
930 	GEM_BANK1_WRITE_4(sc, GEM_TX_RING_PTR_HI, 0);
931 	GEM_BANK1_WRITE_4(sc, GEM_TX_RING_PTR_LO, GEM_CDTXADDR(sc, 0));
932 
933 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_HI, 0);
934 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_LO, GEM_CDRXADDR(sc, 0));
935 #ifdef GEM_DEBUG
936 	CTR3(KTR_GEM, "loading RX ring %lx, TX ring %lx, cddma %lx",
937 	    GEM_CDRXADDR(sc, 0), GEM_CDTXADDR(sc, 0), sc->sc_cddma);
938 #endif
939 
940 	/* step 8.  Global Configuration & Interrupt Mask */
941 	GEM_BANK1_WRITE_4(sc, GEM_INTMASK,
942 	    ~(GEM_INTR_TX_INTME | GEM_INTR_TX_EMPTY | GEM_INTR_RX_DONE |
943 	    GEM_INTR_RX_NOBUF | GEM_INTR_RX_TAG_ERR | GEM_INTR_PERR |
944 	    GEM_INTR_BERR
945 #ifdef GEM_DEBUG
946 	    | GEM_INTR_PCS | GEM_INTR_MIF
947 #endif
948 	    ));
949 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_MASK,
950 	    GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT);
951 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_MASK,
952 	    GEM_MAC_TX_XMIT_DONE | GEM_MAC_TX_DEFER_EXP);
953 #ifdef GEM_DEBUG
954 	GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_MASK,
955 	    ~(GEM_MAC_PAUSED | GEM_MAC_PAUSE | GEM_MAC_RESUME));
956 #else
957 	GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_MASK,
958 	    GEM_MAC_PAUSED | GEM_MAC_PAUSE | GEM_MAC_RESUME);
959 #endif
960 
961 	/* step 9.  ETX Configuration: use mostly default values. */
962 
963 	/* Enable DMA. */
964 	v = gem_ringsize(GEM_NTXDESC /* XXX */);
965 	v |= ((sc->sc_variant == GEM_SUN_ERI ? 0x100 : 0x4ff) << 10) &
966 	    GEM_TX_CONFIG_TXFIFO_TH;
967 	GEM_BANK1_WRITE_4(sc, GEM_TX_CONFIG, v | GEM_TX_CONFIG_TXDMA_EN);
968 
969 	/* step 10.  ERX Configuration */
970 
971 	/* Encode Receive Descriptor ring size. */
972 	v = gem_ringsize(GEM_NRXDESC /* XXX */);
973 	/* RX TCP/UDP checksum offset */
974 	v |= ((ETHER_HDR_LEN + sizeof(struct ip)) <<
975 	    GEM_RX_CONFIG_CXM_START_SHFT);
976 
977 	/* Enable DMA. */
978 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG,
979 	    v | (GEM_THRSH_1024 << GEM_RX_CONFIG_FIFO_THRS_SHIFT) |
980 	    (2 << GEM_RX_CONFIG_FBOFF_SHFT) | GEM_RX_CONFIG_RXDMA_EN);
981 
982 	GEM_BANK1_WRITE_4(sc, GEM_RX_BLANKING,
983 	    (6 << GEM_RX_BLANKING_TIME_SHIFT) | 6);
984 
985 	/*
986 	 * The following value is for an OFF Threshold of about 3/4 full
987 	 * and an ON Threshold of 1/4 full.
988 	 */
989 	GEM_BANK1_WRITE_4(sc, GEM_RX_PAUSE_THRESH,
990 	    (3 * sc->sc_rxfifosize / 256) |
991 	    ((sc->sc_rxfifosize / 256) << 12));
992 
993 	/* step 11.  Configure Media. */
994 
995 	/* step 12.  RX_MAC Configuration Register */
996 	v = GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG);
997 	v |= GEM_MAC_RX_ENABLE | GEM_MAC_RX_STRIP_CRC;
998 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, 0);
999 	GEM_BANK1_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
1000 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1001 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_ENABLE, 0))
1002 		device_printf(sc->sc_dev, "cannot configure RX MAC\n");
1003 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, v);
1004 
1005 	/* step 13. TX_MAC Configuration Register */
1006 	v = GEM_BANK1_READ_4(sc, GEM_MAC_TX_CONFIG);
1007 	v |= GEM_MAC_TX_ENABLE;
1008 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG, 0);
1009 	GEM_BANK1_BARRIER(sc, GEM_MAC_TX_CONFIG, 4,
1010 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1011 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_TX_CONFIG, GEM_MAC_TX_ENABLE, 0))
1012 		device_printf(sc->sc_dev, "cannot configure TX MAC\n");
1013 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG, v);
1014 
1015 	/* step 14.  Issue Transmit Pending command. */
1016 
1017 	/* step 15.  Give the reciever a swift kick. */
1018 	GEM_BANK1_WRITE_4(sc, GEM_RX_KICK, GEM_NRXDESC - 4);
1019 
1020 	ifp->if_drv_flags |= IFF_DRV_RUNNING;
1021 	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
1022 
1023 	mii_mediachg(sc->sc_mii);
1024 
1025 	/* Start the one second timer. */
1026 	sc->sc_wdog_timer = 0;
1027 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
1028 }
1029 
1030 static int
1031 gem_load_txmbuf(struct gem_softc *sc, struct mbuf **m_head)
1032 {
1033 	bus_dma_segment_t txsegs[GEM_NTXSEGS];
1034 	struct gem_txsoft *txs;
1035 	struct ip *ip;
1036 	struct mbuf *m;
1037 	uint64_t cflags, flags;
1038 	int error, nexttx, nsegs, offset, seg;
1039 
1040 	/* Get a work queue entry. */
1041 	if ((txs = STAILQ_FIRST(&sc->sc_txfreeq)) == NULL) {
1042 		/* Ran out of descriptors. */
1043 		return (ENOBUFS);
1044 	}
1045 
1046 	cflags = 0;
1047 	if (((*m_head)->m_pkthdr.csum_flags & sc->sc_csum_features) != 0) {
1048 		if (M_WRITABLE(*m_head) == 0) {
1049 			m = m_dup(*m_head, M_DONTWAIT);
1050 			m_freem(*m_head);
1051 			*m_head = m;
1052 			if (m == NULL)
1053 				return (ENOBUFS);
1054 		}
1055 		offset = sizeof(struct ether_header);
1056 		m = m_pullup(*m_head, offset + sizeof(struct ip));
1057 		if (m == NULL) {
1058 			*m_head = NULL;
1059 			return (ENOBUFS);
1060 		}
1061 		ip = (struct ip *)(mtod(m, caddr_t) + offset);
1062 		offset += (ip->ip_hl << 2);
1063 		cflags = offset << GEM_TD_CXSUM_STARTSHFT |
1064 		    ((offset + m->m_pkthdr.csum_data) <<
1065 		    GEM_TD_CXSUM_STUFFSHFT) | GEM_TD_CXSUM_ENABLE;
1066 		*m_head = m;
1067 	}
1068 
1069 	error = bus_dmamap_load_mbuf_sg(sc->sc_tdmatag, txs->txs_dmamap,
1070 	    *m_head, txsegs, &nsegs, BUS_DMA_NOWAIT);
1071 	if (error == EFBIG) {
1072 		m = m_collapse(*m_head, M_DONTWAIT, GEM_NTXSEGS);
1073 		if (m == NULL) {
1074 			m_freem(*m_head);
1075 			*m_head = NULL;
1076 			return (ENOBUFS);
1077 		}
1078 		*m_head = m;
1079 		error = bus_dmamap_load_mbuf_sg(sc->sc_tdmatag,
1080 		    txs->txs_dmamap, *m_head, txsegs, &nsegs,
1081 		    BUS_DMA_NOWAIT);
1082 		if (error != 0) {
1083 			m_freem(*m_head);
1084 			*m_head = NULL;
1085 			return (error);
1086 		}
1087 	} else if (error != 0)
1088 		return (error);
1089 	/* If nsegs is wrong then the stack is corrupt. */
1090 	KASSERT(nsegs <= GEM_NTXSEGS,
1091 	    ("%s: too many DMA segments (%d)", __func__, nsegs));
1092 	if (nsegs == 0) {
1093 		m_freem(*m_head);
1094 		*m_head = NULL;
1095 		return (EIO);
1096 	}
1097 
1098 	/*
1099 	 * Ensure we have enough descriptors free to describe
1100 	 * the packet.  Note, we always reserve one descriptor
1101 	 * at the end of the ring as a termination point, in
1102 	 * order to prevent wrap-around.
1103 	 */
1104 	if (nsegs > sc->sc_txfree - 1) {
1105 		txs->txs_ndescs = 0;
1106 		bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
1107 		return (ENOBUFS);
1108 	}
1109 
1110 	txs->txs_ndescs = nsegs;
1111 	txs->txs_firstdesc = sc->sc_txnext;
1112 	nexttx = txs->txs_firstdesc;
1113 	for (seg = 0; seg < nsegs; seg++, nexttx = GEM_NEXTTX(nexttx)) {
1114 #ifdef GEM_DEBUG
1115 		CTR6(KTR_GEM,
1116 		    "%s: mapping seg %d (txd %d), len %lx, addr %#lx (%#lx)",
1117 		    __func__, seg, nexttx, txsegs[seg].ds_len,
1118 		    txsegs[seg].ds_addr,
1119 		    GEM_DMA_WRITE(sc, txsegs[seg].ds_addr));
1120 #endif
1121 		sc->sc_txdescs[nexttx].gd_addr =
1122 		    GEM_DMA_WRITE(sc, txsegs[seg].ds_addr);
1123 		KASSERT(txsegs[seg].ds_len < GEM_TD_BUFSIZE,
1124 		    ("%s: segment size too large!", __func__));
1125 		flags = txsegs[seg].ds_len & GEM_TD_BUFSIZE;
1126 		sc->sc_txdescs[nexttx].gd_flags =
1127 		    GEM_DMA_WRITE(sc, flags | cflags);
1128 		txs->txs_lastdesc = nexttx;
1129 	}
1130 
1131 	/* Set EOP on the last descriptor. */
1132 #ifdef GEM_DEBUG
1133 	CTR3(KTR_GEM, "%s: end of packet at segment %d, TX %d",
1134 	    __func__, seg, nexttx);
1135 #endif
1136 	sc->sc_txdescs[txs->txs_lastdesc].gd_flags |=
1137 	    GEM_DMA_WRITE(sc, GEM_TD_END_OF_PACKET);
1138 
1139 	/* Lastly set SOP on the first descriptor. */
1140 #ifdef GEM_DEBUG
1141 	CTR3(KTR_GEM, "%s: start of packet at segment %d, TX %d",
1142 	    __func__, seg, nexttx);
1143 #endif
1144 	if (++sc->sc_txwin > GEM_NTXSEGS * 2 / 3) {
1145 		sc->sc_txwin = 0;
1146 		flags |= GEM_TD_INTERRUPT_ME;
1147 		sc->sc_txdescs[txs->txs_firstdesc].gd_flags |=
1148 		    GEM_DMA_WRITE(sc, GEM_TD_INTERRUPT_ME |
1149 		    GEM_TD_START_OF_PACKET);
1150 	} else
1151 		sc->sc_txdescs[txs->txs_firstdesc].gd_flags |=
1152 		    GEM_DMA_WRITE(sc, GEM_TD_START_OF_PACKET);
1153 
1154 	/* Sync the DMA map. */
1155 	bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
1156 	    BUS_DMASYNC_PREWRITE);
1157 
1158 #ifdef GEM_DEBUG
1159 	CTR4(KTR_GEM, "%s: setting firstdesc=%d, lastdesc=%d, ndescs=%d",
1160 	    __func__, txs->txs_firstdesc, txs->txs_lastdesc,
1161 	    txs->txs_ndescs);
1162 #endif
1163 	STAILQ_REMOVE_HEAD(&sc->sc_txfreeq, txs_q);
1164 	STAILQ_INSERT_TAIL(&sc->sc_txdirtyq, txs, txs_q);
1165 	txs->txs_mbuf = *m_head;
1166 
1167 	sc->sc_txnext = GEM_NEXTTX(txs->txs_lastdesc);
1168 	sc->sc_txfree -= txs->txs_ndescs;
1169 
1170 	return (0);
1171 }
1172 
1173 static void
1174 gem_init_regs(struct gem_softc *sc)
1175 {
1176 	const u_char *laddr = IF_LLADDR(sc->sc_ifp);
1177 
1178 	/* These registers are not cleared on reset. */
1179 	if ((sc->sc_flags & GEM_INITED) == 0) {
1180 		/* magic values */
1181 		GEM_BANK1_WRITE_4(sc, GEM_MAC_IPG0, 0);
1182 		GEM_BANK1_WRITE_4(sc, GEM_MAC_IPG1, 8);
1183 		GEM_BANK1_WRITE_4(sc, GEM_MAC_IPG2, 4);
1184 
1185 		GEM_BANK1_WRITE_4(sc, GEM_MAC_MAC_MIN_FRAME, ETHER_MIN_LEN);
1186 		/* max frame and max burst size */
1187 		GEM_BANK1_WRITE_4(sc, GEM_MAC_MAC_MAX_FRAME,
1188 		    (ETHER_MAX_LEN + ETHER_VLAN_ENCAP_LEN) | (0x2000 << 16));
1189 
1190 		GEM_BANK1_WRITE_4(sc, GEM_MAC_PREAMBLE_LEN, 0x7);
1191 		GEM_BANK1_WRITE_4(sc, GEM_MAC_JAM_SIZE, 0x4);
1192 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ATTEMPT_LIMIT, 0x10);
1193 		/* dunno... */
1194 		GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_TYPE, 0x8088);
1195 		GEM_BANK1_WRITE_4(sc, GEM_MAC_RANDOM_SEED,
1196 		    ((laddr[5] << 8) | laddr[4]) & 0x3ff);
1197 
1198 		/* secondary MAC address: 0:0:0:0:0:0 */
1199 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR3, 0);
1200 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR4, 0);
1201 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR5, 0);
1202 
1203 		/* MAC control address: 01:80:c2:00:00:01 */
1204 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR6, 0x0001);
1205 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR7, 0xc200);
1206 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR8, 0x0180);
1207 
1208 		/* MAC filter address: 0:0:0:0:0:0 */
1209 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR_FILTER0, 0);
1210 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR_FILTER1, 0);
1211 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR_FILTER2, 0);
1212 
1213 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADR_FLT_MASK1_2, 0);
1214 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADR_FLT_MASK0, 0);
1215 
1216 		sc->sc_flags |= GEM_INITED;
1217 	}
1218 
1219 	/* Counters need to be zeroed. */
1220 	GEM_BANK1_WRITE_4(sc, GEM_MAC_NORM_COLL_CNT, 0);
1221 	GEM_BANK1_WRITE_4(sc, GEM_MAC_FIRST_COLL_CNT, 0);
1222 	GEM_BANK1_WRITE_4(sc, GEM_MAC_EXCESS_COLL_CNT, 0);
1223 	GEM_BANK1_WRITE_4(sc, GEM_MAC_LATE_COLL_CNT, 0);
1224 	GEM_BANK1_WRITE_4(sc, GEM_MAC_DEFER_TMR_CNT, 0);
1225 	GEM_BANK1_WRITE_4(sc, GEM_MAC_PEAK_ATTEMPTS, 0);
1226 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_FRAME_COUNT, 0);
1227 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_LEN_ERR_CNT, 0);
1228 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_ALIGN_ERR, 0);
1229 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CRC_ERR_CNT, 0);
1230 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CODE_VIOL, 0);
1231 
1232 	/* Set XOFF PAUSE time. */
1233 	GEM_BANK1_WRITE_4(sc, GEM_MAC_SEND_PAUSE_CMD, 0x1BF0);
1234 
1235 	/*
1236 	 * Set the internal arbitration to "infinite" bursts of the
1237 	 * maximum length of 31 * 64 bytes so DMA transfers aren't
1238 	 * split up in cache line size chunks.  This greatly improves
1239 	 * especially RX performance.
1240 	 * Enable silicon bug workarounds for the Apple variants.
1241 	 */
1242 	GEM_BANK1_WRITE_4(sc, GEM_CONFIG,
1243 	    GEM_CONFIG_TXDMA_LIMIT | GEM_CONFIG_RXDMA_LIMIT |
1244 	    GEM_CONFIG_BURST_INF | (GEM_IS_APPLE(sc) ?
1245 	    GEM_CONFIG_RONPAULBIT | GEM_CONFIG_BUG2FIX : 0));
1246 
1247 	/* Set the station address. */
1248 	GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR0, (laddr[4] << 8) | laddr[5]);
1249 	GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR1, (laddr[2] << 8) | laddr[3]);
1250 	GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR2, (laddr[0] << 8) | laddr[1]);
1251 
1252 	/* Enable MII outputs. */
1253 	GEM_BANK1_WRITE_4(sc, GEM_MAC_XIF_CONFIG, GEM_MAC_XIF_TX_MII_ENA);
1254 }
1255 
1256 static void
1257 gem_start(struct ifnet *ifp)
1258 {
1259 	struct gem_softc *sc = ifp->if_softc;
1260 
1261 	GEM_LOCK(sc);
1262 	gem_start_locked(ifp);
1263 	GEM_UNLOCK(sc);
1264 }
1265 
1266 static void
1267 gem_start_locked(struct ifnet *ifp)
1268 {
1269 	struct gem_softc *sc = ifp->if_softc;
1270 	struct mbuf *m;
1271 	int ntx;
1272 
1273 	if ((ifp->if_drv_flags & (IFF_DRV_RUNNING | IFF_DRV_OACTIVE)) !=
1274 	    IFF_DRV_RUNNING || (sc->sc_flags & GEM_LINK) == 0)
1275 		return;
1276 
1277 #ifdef GEM_DEBUG
1278 	CTR4(KTR_GEM, "%s: %s: txfree %d, txnext %d",
1279 	    device_get_name(sc->sc_dev), __func__, sc->sc_txfree,
1280 	    sc->sc_txnext);
1281 #endif
1282 	ntx = 0;
1283 	for (; !IFQ_DRV_IS_EMPTY(&ifp->if_snd) && sc->sc_txfree > 1;) {
1284 		IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
1285 		if (m == NULL)
1286 			break;
1287 		if (gem_load_txmbuf(sc, &m) != 0) {
1288 			if (m == NULL)
1289 				break;
1290 			ifp->if_drv_flags |= IFF_DRV_OACTIVE;
1291 			IFQ_DRV_PREPEND(&ifp->if_snd, m);
1292 			break;
1293 		}
1294 		ntx++;
1295 		/* Kick the transmitter. */
1296 #ifdef GEM_DEBUG
1297 		CTR3(KTR_GEM, "%s: %s: kicking TX %d",
1298 		    device_get_name(sc->sc_dev), __func__, sc->sc_txnext);
1299 #endif
1300 		GEM_CDSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1301 		GEM_BANK1_WRITE_4(sc, GEM_TX_KICK, sc->sc_txnext);
1302 
1303 		BPF_MTAP(ifp, m);
1304 	}
1305 
1306 	if (ntx > 0) {
1307 #ifdef GEM_DEBUG
1308 		CTR2(KTR_GEM, "%s: packets enqueued, OWN on %d",
1309 		    device_get_name(sc->sc_dev), sc->sc_txnext);
1310 #endif
1311 
1312 		/* Set a watchdog timer in case the chip flakes out. */
1313 		sc->sc_wdog_timer = 5;
1314 #ifdef GEM_DEBUG
1315 		CTR3(KTR_GEM, "%s: %s: watchdog %d",
1316 		    device_get_name(sc->sc_dev), __func__,
1317 		    sc->sc_wdog_timer);
1318 #endif
1319 	}
1320 }
1321 
1322 static void
1323 gem_tint(struct gem_softc *sc)
1324 {
1325 	struct ifnet *ifp = sc->sc_ifp;
1326 	struct gem_txsoft *txs;
1327 	int txlast, progress;
1328 #ifdef GEM_DEBUG
1329 	int i;
1330 
1331 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
1332 #endif
1333 
1334 	/*
1335 	 * Go through our TX list and free mbufs for those
1336 	 * frames that have been transmitted.
1337 	 */
1338 	progress = 0;
1339 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD);
1340 	while ((txs = STAILQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
1341 
1342 #ifdef GEM_DEBUG
1343 		if ((ifp->if_flags & IFF_DEBUG) != 0) {
1344 			printf("    txsoft %p transmit chain:\n", txs);
1345 			for (i = txs->txs_firstdesc;; i = GEM_NEXTTX(i)) {
1346 				printf("descriptor %d: ", i);
1347 				printf("gd_flags: 0x%016llx\t",
1348 				    (long long)GEM_DMA_READ(sc,
1349 				    sc->sc_txdescs[i].gd_flags));
1350 				printf("gd_addr: 0x%016llx\n",
1351 				    (long long)GEM_DMA_READ(sc,
1352 				    sc->sc_txdescs[i].gd_addr));
1353 				if (i == txs->txs_lastdesc)
1354 					break;
1355 			}
1356 		}
1357 #endif
1358 
1359 		/*
1360 		 * In theory, we could harvest some descriptors before
1361 		 * the ring is empty, but that's a bit complicated.
1362 		 *
1363 		 * GEM_TX_COMPLETION points to the last descriptor
1364 		 * processed + 1.
1365 		 */
1366 		txlast = GEM_BANK1_READ_4(sc, GEM_TX_COMPLETION);
1367 #ifdef GEM_DEBUG
1368 		CTR4(KTR_GEM, "%s: txs->txs_firstdesc = %d, "
1369 		    "txs->txs_lastdesc = %d, txlast = %d",
1370 		    __func__, txs->txs_firstdesc, txs->txs_lastdesc, txlast);
1371 #endif
1372 		if (txs->txs_firstdesc <= txs->txs_lastdesc) {
1373 			if ((txlast >= txs->txs_firstdesc) &&
1374 			    (txlast <= txs->txs_lastdesc))
1375 				break;
1376 		} else {
1377 			/* Ick -- this command wraps. */
1378 			if ((txlast >= txs->txs_firstdesc) ||
1379 			    (txlast <= txs->txs_lastdesc))
1380 				break;
1381 		}
1382 
1383 #ifdef GEM_DEBUG
1384 		CTR1(KTR_GEM, "%s: releasing a descriptor", __func__);
1385 #endif
1386 		STAILQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
1387 
1388 		sc->sc_txfree += txs->txs_ndescs;
1389 
1390 		bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
1391 		    BUS_DMASYNC_POSTWRITE);
1392 		bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
1393 		if (txs->txs_mbuf != NULL) {
1394 			m_freem(txs->txs_mbuf);
1395 			txs->txs_mbuf = NULL;
1396 		}
1397 
1398 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
1399 
1400 		ifp->if_opackets++;
1401 		progress = 1;
1402 	}
1403 
1404 #ifdef GEM_DEBUG
1405 	CTR4(KTR_GEM, "%s: GEM_TX_STATE_MACHINE %x GEM_TX_DATA_PTR %llx "
1406 	    "GEM_TX_COMPLETION %x",
1407 	    __func__, GEM_BANK1_READ_4(sc, GEM_TX_STATE_MACHINE),
1408 	    ((long long)GEM_BANK1_READ_4(sc, GEM_TX_DATA_PTR_HI) << 32) |
1409 	    GEM_BANK1_READ_4(sc, GEM_TX_DATA_PTR_LO),
1410 	    GEM_BANK1_READ_4(sc, GEM_TX_COMPLETION));
1411 #endif
1412 
1413 	if (progress) {
1414 		if (sc->sc_txfree == GEM_NTXDESC - 1)
1415 			sc->sc_txwin = 0;
1416 
1417 		/*
1418 		 * We freed some descriptors, so reset IFF_DRV_OACTIVE
1419 		 * and restart.
1420 		 */
1421 		ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
1422 		sc->sc_wdog_timer = STAILQ_EMPTY(&sc->sc_txdirtyq) ? 0 : 5;
1423 
1424 		gem_start_locked(ifp);
1425 	}
1426 
1427 #ifdef GEM_DEBUG
1428 	CTR3(KTR_GEM, "%s: %s: watchdog %d",
1429 	    device_get_name(sc->sc_dev), __func__, sc->sc_wdog_timer);
1430 #endif
1431 }
1432 
1433 #ifdef GEM_RINT_TIMEOUT
1434 static void
1435 gem_rint_timeout(void *arg)
1436 {
1437 	struct gem_softc *sc = arg;
1438 
1439 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1440 	gem_rint(sc);
1441 }
1442 #endif
1443 
1444 static void
1445 gem_rint(struct gem_softc *sc)
1446 {
1447 	struct ifnet *ifp = sc->sc_ifp;
1448 	struct mbuf *m;
1449 	uint64_t rxstat;
1450 	uint32_t rxcomp;
1451 
1452 #ifdef GEM_RINT_TIMEOUT
1453 	callout_stop(&sc->sc_rx_ch);
1454 #endif
1455 #ifdef GEM_DEBUG
1456 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
1457 #endif
1458 
1459 	/*
1460 	 * Read the completion register once.  This limits
1461 	 * how long the following loop can execute.
1462 	 */
1463 	rxcomp = GEM_BANK1_READ_4(sc, GEM_RX_COMPLETION);
1464 
1465 #ifdef GEM_DEBUG
1466 	CTR3(KTR_GEM, "%s: sc->rxptr %d, complete %d",
1467 	    __func__, sc->sc_rxptr, rxcomp);
1468 #endif
1469 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD);
1470 	for (; sc->sc_rxptr != rxcomp;) {
1471 		m = sc->sc_rxsoft[sc->sc_rxptr].rxs_mbuf;
1472 		rxstat = GEM_DMA_READ(sc,
1473 		    sc->sc_rxdescs[sc->sc_rxptr].gd_flags);
1474 
1475 		if (rxstat & GEM_RD_OWN) {
1476 #ifdef GEM_RINT_TIMEOUT
1477 			/*
1478 			 * The descriptor is still marked as owned, although
1479 			 * it is supposed to have completed.  This has been
1480 			 * observed on some machines.  Just exiting here
1481 			 * might leave the packet sitting around until another
1482 			 * one arrives to trigger a new interrupt, which is
1483 			 * generally undesirable, so set up a timeout.
1484 			 */
1485 			callout_reset(&sc->sc_rx_ch, GEM_RXOWN_TICKS,
1486 			    gem_rint_timeout, sc);
1487 #endif
1488 			m = NULL;
1489 			goto kickit;
1490 		}
1491 
1492 		if (rxstat & GEM_RD_BAD_CRC) {
1493 			ifp->if_ierrors++;
1494 			device_printf(sc->sc_dev, "receive error: CRC error\n");
1495 			GEM_INIT_RXDESC(sc, sc->sc_rxptr);
1496 			m = NULL;
1497 			goto kickit;
1498 		}
1499 
1500 #ifdef GEM_DEBUG
1501 		if ((ifp->if_flags & IFF_DEBUG) != 0) {
1502 			printf("    rxsoft %p descriptor %d: ",
1503 			    &sc->sc_rxsoft[sc->sc_rxptr], sc->sc_rxptr);
1504 			printf("gd_flags: 0x%016llx\t",
1505 			    (long long)GEM_DMA_READ(sc,
1506 			    sc->sc_rxdescs[sc->sc_rxptr].gd_flags));
1507 			printf("gd_addr: 0x%016llx\n",
1508 			    (long long)GEM_DMA_READ(sc,
1509 			    sc->sc_rxdescs[sc->sc_rxptr].gd_addr));
1510 		}
1511 #endif
1512 
1513 		/*
1514 		 * Allocate a new mbuf cluster.  If that fails, we are
1515 		 * out of memory, and must drop the packet and recycle
1516 		 * the buffer that's already attached to this descriptor.
1517 		 */
1518 		if (gem_add_rxbuf(sc, sc->sc_rxptr) != 0) {
1519 			ifp->if_ierrors++;
1520 			GEM_INIT_RXDESC(sc, sc->sc_rxptr);
1521 			m = NULL;
1522 		}
1523 
1524  kickit:
1525 		/*
1526 		 * Update the RX kick register.  This register has to point
1527 		 * to the descriptor after the last valid one (before the
1528 		 * current batch) and must be incremented in multiples of
1529 		 * 4 (because the DMA engine fetches/updates descriptors
1530 		 * in batches of 4).
1531 		 */
1532 		sc->sc_rxptr = GEM_NEXTRX(sc->sc_rxptr);
1533 		if ((sc->sc_rxptr % 4) == 0) {
1534 			GEM_CDSYNC(sc,
1535 			    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1536 			GEM_BANK1_WRITE_4(sc, GEM_RX_KICK,
1537 			    (sc->sc_rxptr + GEM_NRXDESC - 4) &
1538 			    GEM_NRXDESC_MASK);
1539 		}
1540 
1541 		if (m == NULL) {
1542 			if (rxstat & GEM_RD_OWN)
1543 				break;
1544 			continue;
1545 		}
1546 
1547 		ifp->if_ipackets++;
1548 		m->m_data += 2; /* We're already off by two */
1549 		m->m_pkthdr.rcvif = ifp;
1550 		m->m_pkthdr.len = m->m_len = GEM_RD_BUFLEN(rxstat);
1551 
1552 		if ((ifp->if_capenable & IFCAP_RXCSUM) != 0)
1553 			gem_rxcksum(m, rxstat);
1554 
1555 		/* Pass it on. */
1556 		GEM_UNLOCK(sc);
1557 		(*ifp->if_input)(ifp, m);
1558 		GEM_LOCK(sc);
1559 	}
1560 
1561 #ifdef GEM_DEBUG
1562 	CTR3(KTR_GEM, "%s: done sc->rxptr %d, complete %d", __func__,
1563 	    sc->sc_rxptr, GEM_BANK1_READ_4(sc, GEM_RX_COMPLETION));
1564 #endif
1565 }
1566 
1567 static int
1568 gem_add_rxbuf(struct gem_softc *sc, int idx)
1569 {
1570 	struct gem_rxsoft *rxs = &sc->sc_rxsoft[idx];
1571 	struct mbuf *m;
1572 	bus_dma_segment_t segs[1];
1573 	int error, nsegs;
1574 
1575 	m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
1576 	if (m == NULL)
1577 		return (ENOBUFS);
1578 	m->m_len = m->m_pkthdr.len = m->m_ext.ext_size;
1579 
1580 #ifdef GEM_DEBUG
1581 	/* Bzero the packet to check DMA. */
1582 	memset(m->m_ext.ext_buf, 0, m->m_ext.ext_size);
1583 #endif
1584 
1585 	if (rxs->rxs_mbuf != NULL) {
1586 		bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
1587 		    BUS_DMASYNC_POSTREAD);
1588 		bus_dmamap_unload(sc->sc_rdmatag, rxs->rxs_dmamap);
1589 	}
1590 
1591 	error = bus_dmamap_load_mbuf_sg(sc->sc_rdmatag, rxs->rxs_dmamap,
1592 	    m, segs, &nsegs, BUS_DMA_NOWAIT);
1593 	if (error != 0) {
1594 		device_printf(sc->sc_dev,
1595 		    "cannot load RS DMA map %d, error = %d\n", idx, error);
1596 		m_freem(m);
1597 		return (error);
1598 	}
1599 	/* If nsegs is wrong then the stack is corrupt. */
1600 	KASSERT(nsegs == 1,
1601 	    ("%s: too many DMA segments (%d)", __func__, nsegs));
1602 	rxs->rxs_mbuf = m;
1603 	rxs->rxs_paddr = segs[0].ds_addr;
1604 
1605 	bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
1606 	    BUS_DMASYNC_PREREAD);
1607 
1608 	GEM_INIT_RXDESC(sc, idx);
1609 
1610 	return (0);
1611 }
1612 
1613 static void
1614 gem_eint(struct gem_softc *sc, u_int status)
1615 {
1616 
1617 	sc->sc_ifp->if_ierrors++;
1618 	if ((status & GEM_INTR_RX_TAG_ERR) != 0) {
1619 		gem_reset_rxdma(sc);
1620 		return;
1621 	}
1622 
1623 	device_printf(sc->sc_dev, "%s: status=%x\n", __func__, status);
1624 }
1625 
1626 void
1627 gem_intr(void *v)
1628 {
1629 	struct gem_softc *sc = v;
1630 	uint32_t status, status2;
1631 
1632 	GEM_LOCK(sc);
1633 	status = GEM_BANK1_READ_4(sc, GEM_STATUS);
1634 
1635 #ifdef GEM_DEBUG
1636 	CTR4(KTR_GEM, "%s: %s: cplt %x, status %x",
1637 	    device_get_name(sc->sc_dev), __func__, (status >> 19),
1638 	    (u_int)status);
1639 
1640 	/*
1641 	 * PCS interrupts must be cleared, otherwise no traffic is passed!
1642 	 */
1643 	if ((status & GEM_INTR_PCS) != 0) {
1644 		status2 =
1645 		    GEM_BANK1_READ_4(sc, GEM_MII_INTERRUP_STATUS) |
1646 		    GEM_BANK1_READ_4(sc, GEM_MII_INTERRUP_STATUS);
1647 		if ((status2 & GEM_MII_INTERRUP_LINK) != 0)
1648 			device_printf(sc->sc_dev,
1649 			    "%s: PCS link status changed\n", __func__);
1650 	}
1651 	if ((status & GEM_MAC_CONTROL_STATUS) != 0) {
1652 		status2 = GEM_BANK1_READ_4(sc, GEM_MAC_CONTROL_STATUS);
1653 		if ((status2 & GEM_MAC_PAUSED) != 0)
1654 			device_printf(sc->sc_dev,
1655 			    "%s: PAUSE received (PAUSE time %d slots)\n",
1656 			    __func__, GEM_MAC_PAUSE_TIME(status2));
1657 		if ((status2 & GEM_MAC_PAUSE) != 0)
1658 			device_printf(sc->sc_dev,
1659 			    "%s: transited to PAUSE state\n", __func__);
1660 		if ((status2 & GEM_MAC_RESUME) != 0)
1661 			device_printf(sc->sc_dev,
1662 			    "%s: transited to non-PAUSE state\n", __func__);
1663 	}
1664 	if ((status & GEM_INTR_MIF) != 0)
1665 		device_printf(sc->sc_dev, "%s: MIF interrupt\n", __func__);
1666 #endif
1667 
1668 	if ((status &
1669 	    (GEM_INTR_RX_TAG_ERR | GEM_INTR_PERR | GEM_INTR_BERR)) != 0)
1670 		gem_eint(sc, status);
1671 
1672 	if ((status & (GEM_INTR_RX_DONE | GEM_INTR_RX_NOBUF)) != 0)
1673 		gem_rint(sc);
1674 
1675 	if ((status & (GEM_INTR_TX_EMPTY | GEM_INTR_TX_INTME)) != 0)
1676 		gem_tint(sc);
1677 
1678 	if (status & GEM_INTR_TX_MAC) {
1679 		status2 = GEM_BANK1_READ_4(sc, GEM_MAC_TX_STATUS);
1680 		if ((status2 &
1681 		    ~(GEM_MAC_TX_XMIT_DONE | GEM_MAC_TX_DEFER_EXP)) != 0)
1682 			device_printf(sc->sc_dev,
1683 			    "MAC TX fault, status %x\n", status2);
1684 		if ((status2 &
1685 		    (GEM_MAC_TX_UNDERRUN | GEM_MAC_TX_PKT_TOO_LONG)) != 0)
1686 			gem_init_locked(sc);
1687 	}
1688 	if (status & GEM_INTR_RX_MAC) {
1689 		status2 = GEM_BANK1_READ_4(sc, GEM_MAC_RX_STATUS);
1690 		/*
1691 		 * At least with GEM_SUN_GEM and some GEM_SUN_ERI
1692 		 * revisions GEM_MAC_RX_OVERFLOW happen often due to a
1693 		 * silicon bug so handle them silently.  Moreover, it's
1694 		 * likely that the receiver has hung so we reset it.
1695 		 */
1696 		if ((status2 & GEM_MAC_RX_OVERFLOW) != 0) {
1697 			sc->sc_ifp->if_ierrors++;
1698 			gem_reset_rxdma(sc);
1699 		} else if ((status2 &
1700 		    ~(GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT)) != 0)
1701 			device_printf(sc->sc_dev,
1702 			    "MAC RX fault, status %x\n", status2);
1703 	}
1704 	GEM_UNLOCK(sc);
1705 }
1706 
1707 static int
1708 gem_watchdog(struct gem_softc *sc)
1709 {
1710 	struct ifnet *ifp = sc->sc_ifp;
1711 
1712 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1713 
1714 #ifdef GEM_DEBUG
1715 	CTR4(KTR_GEM,
1716 	    "%s: GEM_RX_CONFIG %x GEM_MAC_RX_STATUS %x GEM_MAC_RX_CONFIG %x",
1717 	    __func__, GEM_BANK1_READ_4(sc, GEM_RX_CONFIG),
1718 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_STATUS),
1719 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG));
1720 	CTR4(KTR_GEM,
1721 	    "%s: GEM_TX_CONFIG %x GEM_MAC_TX_STATUS %x GEM_MAC_TX_CONFIG %x",
1722 	    __func__, GEM_BANK1_READ_4(sc, GEM_TX_CONFIG),
1723 	    GEM_BANK1_READ_4(sc, GEM_MAC_TX_STATUS),
1724 	    GEM_BANK1_READ_4(sc, GEM_MAC_TX_CONFIG));
1725 #endif
1726 
1727 	if (sc->sc_wdog_timer == 0 || --sc->sc_wdog_timer != 0)
1728 		return (0);
1729 
1730 	if ((sc->sc_flags & GEM_LINK) != 0)
1731 		device_printf(sc->sc_dev, "device timeout\n");
1732 	else if (bootverbose)
1733 		device_printf(sc->sc_dev, "device timeout (no link)\n");
1734 	++ifp->if_oerrors;
1735 
1736 	/* Try to get more packets going. */
1737 	gem_init_locked(sc);
1738 	gem_start_locked(ifp);
1739 	return (EJUSTRETURN);
1740 }
1741 
1742 static void
1743 gem_mifinit(struct gem_softc *sc)
1744 {
1745 
1746 	/* Configure the MIF in frame mode. */
1747 	GEM_BANK1_WRITE_4(sc, GEM_MIF_CONFIG,
1748 	    GEM_BANK1_READ_4(sc, GEM_MIF_CONFIG) & ~GEM_MIF_CONFIG_BB_ENA);
1749 }
1750 
1751 /*
1752  * MII interface
1753  *
1754  * The MII interface supports at least three different operating modes:
1755  *
1756  * Bitbang mode is implemented using data, clock and output enable registers.
1757  *
1758  * Frame mode is implemented by loading a complete frame into the frame
1759  * register and polling the valid bit for completion.
1760  *
1761  * Polling mode uses the frame register but completion is indicated by
1762  * an interrupt.
1763  *
1764  */
1765 int
1766 gem_mii_readreg(device_t dev, int phy, int reg)
1767 {
1768 	struct gem_softc *sc;
1769 	int n;
1770 	uint32_t v;
1771 
1772 #ifdef GEM_DEBUG_PHY
1773 	printf("%s: phy %d reg %d\n", __func__, phy, reg);
1774 #endif
1775 
1776 	sc = device_get_softc(dev);
1777 	if (sc->sc_phyad != -1 && phy != sc->sc_phyad)
1778 		return (0);
1779 
1780 	if ((sc->sc_flags & GEM_SERDES) != 0) {
1781 		switch (reg) {
1782 		case MII_BMCR:
1783 			reg = GEM_MII_CONTROL;
1784 			break;
1785 		case MII_BMSR:
1786 			reg = GEM_MII_STATUS;
1787 			break;
1788 		case MII_PHYIDR1:
1789 		case MII_PHYIDR2:
1790 			return (0);
1791 		case MII_ANAR:
1792 			reg = GEM_MII_ANAR;
1793 			break;
1794 		case MII_ANLPAR:
1795 			reg = GEM_MII_ANLPAR;
1796 			break;
1797 		case MII_EXTSR:
1798 			return (EXTSR_1000XFDX | EXTSR_1000XHDX);
1799 		default:
1800 			device_printf(sc->sc_dev,
1801 			    "%s: unhandled register %d\n", __func__, reg);
1802 			return (0);
1803 		}
1804 		return (GEM_BANK1_READ_4(sc, reg));
1805 	}
1806 
1807 	/* Construct the frame command. */
1808 	v = GEM_MIF_FRAME_READ |
1809 	    (phy << GEM_MIF_PHY_SHIFT) |
1810 	    (reg << GEM_MIF_REG_SHIFT);
1811 
1812 	GEM_BANK1_WRITE_4(sc, GEM_MIF_FRAME, v);
1813 	GEM_BANK1_BARRIER(sc, GEM_MIF_FRAME, 4,
1814 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1815 	for (n = 0; n < 100; n++) {
1816 		DELAY(1);
1817 		v = GEM_BANK1_READ_4(sc, GEM_MIF_FRAME);
1818 		if (v & GEM_MIF_FRAME_TA0)
1819 			return (v & GEM_MIF_FRAME_DATA);
1820 	}
1821 
1822 	device_printf(sc->sc_dev, "%s: timed out\n", __func__);
1823 	return (0);
1824 }
1825 
1826 int
1827 gem_mii_writereg(device_t dev, int phy, int reg, int val)
1828 {
1829 	struct gem_softc *sc;
1830 	int n;
1831 	uint32_t v;
1832 
1833 #ifdef GEM_DEBUG_PHY
1834 	printf("%s: phy %d reg %d val %x\n", phy, reg, val, __func__);
1835 #endif
1836 
1837 	sc = device_get_softc(dev);
1838 	if (sc->sc_phyad != -1 && phy != sc->sc_phyad)
1839 		return (0);
1840 
1841 	if ((sc->sc_flags & GEM_SERDES) != 0) {
1842 		switch (reg) {
1843 		case MII_BMSR:
1844 			reg = GEM_MII_STATUS;
1845 			break;
1846 		case MII_BMCR:
1847 			reg = GEM_MII_CONTROL;
1848 			if ((val & GEM_MII_CONTROL_RESET) == 0)
1849 				break;
1850 			GEM_BANK1_WRITE_4(sc, GEM_MII_CONTROL, val);
1851 			GEM_BANK1_BARRIER(sc, GEM_MII_CONTROL, 4,
1852 			    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1853 			if (!GEM_BANK1_BITWAIT(sc, GEM_MII_CONTROL,
1854 			    GEM_MII_CONTROL_RESET, 0))
1855 				device_printf(sc->sc_dev,
1856 				    "cannot reset PCS\n");
1857 			/* FALLTHROUGH */
1858 		case MII_ANAR:
1859 			GEM_BANK1_WRITE_4(sc, GEM_MII_CONFIG, 0);
1860 			GEM_BANK1_BARRIER(sc, GEM_MII_CONFIG, 4,
1861 			    BUS_SPACE_BARRIER_WRITE);
1862 			GEM_BANK1_WRITE_4(sc, GEM_MII_ANAR, val);
1863 			GEM_BANK1_WRITE_4(sc, GEM_MII_SLINK_CONTROL,
1864 			    GEM_MII_SLINK_LOOPBACK | GEM_MII_SLINK_EN_SYNC_D);
1865 			GEM_BANK1_WRITE_4(sc, GEM_MII_CONFIG,
1866 			    GEM_MII_CONFIG_ENABLE);
1867 			return (0);
1868 		case MII_ANLPAR:
1869 			reg = GEM_MII_ANLPAR;
1870 			break;
1871 		default:
1872 			device_printf(sc->sc_dev,
1873 			    "%s: unhandled register %d\n", __func__, reg);
1874 			return (0);
1875 		}
1876 		GEM_BANK1_WRITE_4(sc, reg, val);
1877 		return (0);
1878 	}
1879 
1880 	/* Construct the frame command. */
1881 	v = GEM_MIF_FRAME_WRITE |
1882 	    (phy << GEM_MIF_PHY_SHIFT) |
1883 	    (reg << GEM_MIF_REG_SHIFT) |
1884 	    (val & GEM_MIF_FRAME_DATA);
1885 
1886 	GEM_BANK1_WRITE_4(sc, GEM_MIF_FRAME, v);
1887 	GEM_BANK1_BARRIER(sc, GEM_MIF_FRAME, 4,
1888 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1889 	for (n = 0; n < 100; n++) {
1890 		DELAY(1);
1891 		v = GEM_BANK1_READ_4(sc, GEM_MIF_FRAME);
1892 		if (v & GEM_MIF_FRAME_TA0)
1893 			return (1);
1894 	}
1895 
1896 	device_printf(sc->sc_dev, "%s: timed out\n", __func__);
1897 	return (0);
1898 }
1899 
1900 void
1901 gem_mii_statchg(device_t dev)
1902 {
1903 	struct gem_softc *sc;
1904 	int gigabit;
1905 	uint32_t rxcfg, txcfg, v;
1906 
1907 	sc = device_get_softc(dev);
1908 
1909 #ifdef GEM_DEBUG
1910 	if ((sc->sc_ifp->if_flags & IFF_DEBUG) != 0)
1911 		device_printf(sc->sc_dev, "%s: status change: PHY = %d\n",
1912 		    __func__, sc->sc_phyad);
1913 #endif
1914 
1915 	if ((sc->sc_mii->mii_media_status & IFM_ACTIVE) != 0 &&
1916 	    IFM_SUBTYPE(sc->sc_mii->mii_media_active) != IFM_NONE)
1917 		sc->sc_flags |= GEM_LINK;
1918 	else
1919 		sc->sc_flags &= ~GEM_LINK;
1920 
1921 	switch (IFM_SUBTYPE(sc->sc_mii->mii_media_active)) {
1922 	case IFM_1000_SX:
1923 	case IFM_1000_LX:
1924 	case IFM_1000_CX:
1925 	case IFM_1000_T:
1926 		gigabit = 1;
1927 		break;
1928 	default:
1929 		gigabit = 0;
1930 	}
1931 
1932 	/*
1933 	 * The configuration done here corresponds to the steps F) and
1934 	 * G) and as far as enabling of RX and TX MAC goes also step H)
1935 	 * of the initialization sequence outlined in section 3.2.1 of
1936 	 * the GEM Gigabit Ethernet ASIC Specification.
1937 	 */
1938 
1939 	rxcfg = GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG);
1940 	rxcfg &= ~(GEM_MAC_RX_CARR_EXTEND | GEM_MAC_RX_ENABLE);
1941 	txcfg = GEM_MAC_TX_ENA_IPG0 | GEM_MAC_TX_NGU | GEM_MAC_TX_NGU_LIMIT;
1942 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) != 0)
1943 		txcfg |= GEM_MAC_TX_IGN_CARRIER | GEM_MAC_TX_IGN_COLLIS;
1944 	else if (gigabit != 0) {
1945 		rxcfg |= GEM_MAC_RX_CARR_EXTEND;
1946 		txcfg |= GEM_MAC_TX_CARR_EXTEND;
1947 	}
1948 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG, 0);
1949 	GEM_BANK1_BARRIER(sc, GEM_MAC_TX_CONFIG, 4,
1950 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1951 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_TX_CONFIG, GEM_MAC_TX_ENABLE, 0))
1952 		device_printf(sc->sc_dev, "cannot disable TX MAC\n");
1953 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG, txcfg);
1954 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, 0);
1955 	GEM_BANK1_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
1956 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1957 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_ENABLE, 0))
1958 		device_printf(sc->sc_dev, "cannot disable RX MAC\n");
1959 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, rxcfg);
1960 
1961 	v = GEM_BANK1_READ_4(sc, GEM_MAC_CONTROL_CONFIG) &
1962 	    ~(GEM_MAC_CC_RX_PAUSE | GEM_MAC_CC_TX_PAUSE);
1963 #ifdef notyet
1964 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
1965 	    IFM_ETH_RXPAUSE) != 0)
1966 		v |= GEM_MAC_CC_RX_PAUSE;
1967 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
1968 	    IFM_ETH_TXPAUSE) != 0)
1969 		v |= GEM_MAC_CC_TX_PAUSE;
1970 #endif
1971 	GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_CONFIG, v);
1972 
1973 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) == 0 &&
1974 	    gigabit != 0)
1975 		GEM_BANK1_WRITE_4(sc, GEM_MAC_SLOT_TIME,
1976 		    GEM_MAC_SLOT_TIME_CARR_EXTEND);
1977 	else
1978 		GEM_BANK1_WRITE_4(sc, GEM_MAC_SLOT_TIME,
1979 		    GEM_MAC_SLOT_TIME_NORMAL);
1980 
1981 	/* XIF Configuration */
1982 	v = GEM_MAC_XIF_LINK_LED;
1983 	v |= GEM_MAC_XIF_TX_MII_ENA;
1984 	if ((sc->sc_flags & GEM_SERDES) == 0) {
1985 		if ((GEM_BANK1_READ_4(sc, GEM_MIF_CONFIG) &
1986 		    GEM_MIF_CONFIG_PHY_SEL) != 0) {
1987 			/* External MII needs echo disable if half duplex. */
1988 		    	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
1989 			    IFM_FDX) == 0)
1990 				v |= GEM_MAC_XIF_ECHO_DISABL;
1991 		} else
1992 			/*
1993 			 * Internal MII needs buffer enable.
1994 			 * XXX buffer enable makes only sense for an
1995 			 * external PHY.
1996 			 */
1997 			v |= GEM_MAC_XIF_MII_BUF_ENA;
1998 	}
1999 	if (gigabit != 0)
2000 		v |= GEM_MAC_XIF_GMII_MODE;
2001 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) != 0)
2002 		v |= GEM_MAC_XIF_FDPLX_LED;
2003 	GEM_BANK1_WRITE_4(sc, GEM_MAC_XIF_CONFIG, v);
2004 
2005 	if ((sc->sc_ifp->if_drv_flags & IFF_DRV_RUNNING) != 0 &&
2006 	    (sc->sc_flags & GEM_LINK) != 0) {
2007 		GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG,
2008 		    txcfg | GEM_MAC_TX_ENABLE);
2009 		GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG,
2010 		    rxcfg | GEM_MAC_RX_ENABLE);
2011 	}
2012 }
2013 
2014 int
2015 gem_mediachange(struct ifnet *ifp)
2016 {
2017 	struct gem_softc *sc = ifp->if_softc;
2018 	int error;
2019 
2020 	/* XXX add support for serial media. */
2021 
2022 	GEM_LOCK(sc);
2023 	error = mii_mediachg(sc->sc_mii);
2024 	GEM_UNLOCK(sc);
2025 	return (error);
2026 }
2027 
2028 void
2029 gem_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
2030 {
2031 	struct gem_softc *sc = ifp->if_softc;
2032 
2033 	GEM_LOCK(sc);
2034 	if ((ifp->if_flags & IFF_UP) == 0) {
2035 		GEM_UNLOCK(sc);
2036 		return;
2037 	}
2038 
2039 	mii_pollstat(sc->sc_mii);
2040 	ifmr->ifm_active = sc->sc_mii->mii_media_active;
2041 	ifmr->ifm_status = sc->sc_mii->mii_media_status;
2042 	GEM_UNLOCK(sc);
2043 }
2044 
2045 static int
2046 gem_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
2047 {
2048 	struct gem_softc *sc = ifp->if_softc;
2049 	struct ifreq *ifr = (struct ifreq *)data;
2050 	int error;
2051 
2052 	error = 0;
2053 	switch (cmd) {
2054 	case SIOCSIFFLAGS:
2055 		GEM_LOCK(sc);
2056 		if ((ifp->if_flags & IFF_UP) != 0) {
2057 			if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0 &&
2058 			    ((ifp->if_flags ^ sc->sc_ifflags) &
2059 			    (IFF_ALLMULTI | IFF_PROMISC)) != 0)
2060 				gem_setladrf(sc);
2061 			else
2062 				gem_init_locked(sc);
2063 		} else if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
2064 			gem_stop(ifp, 0);
2065 		if ((ifp->if_flags & IFF_LINK0) != 0)
2066 			sc->sc_csum_features |= CSUM_UDP;
2067 		else
2068 			sc->sc_csum_features &= ~CSUM_UDP;
2069 		if ((ifp->if_capenable & IFCAP_TXCSUM) != 0)
2070 			ifp->if_hwassist = sc->sc_csum_features;
2071 		sc->sc_ifflags = ifp->if_flags;
2072 		GEM_UNLOCK(sc);
2073 		break;
2074 	case SIOCADDMULTI:
2075 	case SIOCDELMULTI:
2076 		GEM_LOCK(sc);
2077 		gem_setladrf(sc);
2078 		GEM_UNLOCK(sc);
2079 		break;
2080 	case SIOCGIFMEDIA:
2081 	case SIOCSIFMEDIA:
2082 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii->mii_media, cmd);
2083 		break;
2084 	case SIOCSIFCAP:
2085 		GEM_LOCK(sc);
2086 		ifp->if_capenable = ifr->ifr_reqcap;
2087 		if ((ifp->if_capenable & IFCAP_TXCSUM) != 0)
2088 			ifp->if_hwassist = sc->sc_csum_features;
2089 		else
2090 			ifp->if_hwassist = 0;
2091 		GEM_UNLOCK(sc);
2092 		break;
2093 	default:
2094 		error = ether_ioctl(ifp, cmd, data);
2095 		break;
2096 	}
2097 
2098 	return (error);
2099 }
2100 
2101 static void
2102 gem_setladrf(struct gem_softc *sc)
2103 {
2104 	struct ifnet *ifp = sc->sc_ifp;
2105 	struct ifmultiaddr *inm;
2106 	int i;
2107 	uint32_t hash[16];
2108 	uint32_t crc, v;
2109 
2110 	GEM_LOCK_ASSERT(sc, MA_OWNED);
2111 
2112 	/* Get the current RX configuration. */
2113 	v = GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG);
2114 
2115 	/*
2116 	 * Turn off promiscuous mode, promiscuous group mode (all multicast),
2117 	 * and hash filter.  Depending on the case, the right bit will be
2118 	 * enabled.
2119 	 */
2120 	v &= ~(GEM_MAC_RX_PROMISCUOUS | GEM_MAC_RX_HASH_FILTER |
2121 	    GEM_MAC_RX_PROMISC_GRP);
2122 
2123 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, v);
2124 	GEM_BANK1_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
2125 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
2126 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_HASH_FILTER,
2127 	    0))
2128 		device_printf(sc->sc_dev, "cannot disable RX hash filter\n");
2129 
2130 	if ((ifp->if_flags & IFF_PROMISC) != 0) {
2131 		v |= GEM_MAC_RX_PROMISCUOUS;
2132 		goto chipit;
2133 	}
2134 	if ((ifp->if_flags & IFF_ALLMULTI) != 0) {
2135 		v |= GEM_MAC_RX_PROMISC_GRP;
2136 		goto chipit;
2137 	}
2138 
2139 	/*
2140 	 * Set up multicast address filter by passing all multicast
2141 	 * addresses through a crc generator, and then using the high
2142 	 * order 8 bits as an index into the 256 bit logical address
2143 	 * filter.  The high order 4 bits selects the word, while the
2144 	 * other 4 bits select the bit within the word (where bit 0
2145 	 * is the MSB).
2146 	 */
2147 
2148 	/* Clear the hash table. */
2149 	memset(hash, 0, sizeof(hash));
2150 
2151 	IF_ADDR_LOCK(ifp);
2152 	TAILQ_FOREACH(inm, &ifp->if_multiaddrs, ifma_link) {
2153 		if (inm->ifma_addr->sa_family != AF_LINK)
2154 			continue;
2155 		crc = ether_crc32_le(LLADDR((struct sockaddr_dl *)
2156 		    inm->ifma_addr), ETHER_ADDR_LEN);
2157 
2158 		/* We just want the 8 most significant bits. */
2159 		crc >>= 24;
2160 
2161 		/* Set the corresponding bit in the filter. */
2162 		hash[crc >> 4] |= 1 << (15 - (crc & 15));
2163 	}
2164 	IF_ADDR_UNLOCK(ifp);
2165 
2166 	v |= GEM_MAC_RX_HASH_FILTER;
2167 
2168 	/* Now load the hash table into the chip (if we are using it). */
2169 	for (i = 0; i < 16; i++)
2170 		GEM_BANK1_WRITE_4(sc,
2171 		    GEM_MAC_HASH0 + i * (GEM_MAC_HASH1 - GEM_MAC_HASH0),
2172 		    hash[i]);
2173 
2174  chipit:
2175 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, v);
2176 }
2177